Up next: iron curtains

â€œThousands of optical glass fibers form a matrix and run parallel to each other between the two main surfaces of every block,â€� explained its inventor Aron Losonczi. â€œShadows on the lighter side will appear with sharp outlines on the darker one. Even the colours remain the same. This special effect creates the general impression that the thickness and weight of a concrete wall will disappear.â€�

The hope is that the new material will transform the interior appearance of concrete buildings by making them feel light and airy rather than dark and heavy.

This is all well and good, but we're now 18 years overdue for transparent aluminum. The good news is they're apparently getting closer.